The need to install and level objects on uneven or sloping floors has presented a longstanding problem, especially for various types of apparatuses including machines and appliances. Often floors are not plumb or perfectly flat, yet it is important that all the legs of an object contact the floor to provide adequate support and to equally distribute the weight of the object. If all the legs do not contact the floor, many problems can develop. For example, the outer cabinet and frame of an apparatus may become distorted over time due to nonuniform weight support, thereby impairing the proper operation of the apparatus. For example, this is especially true of refrigeration units, freezers, and ice machines which rely on a level installation to achieve proper sealing of their door gaskets. In the case of a motorized apparatus such as a washing machine, inadequate contact of all its legs with the floor is especially problematic because these devices have a tendency to vibrate and “walk” across the floor if the floor is not level. Annoying “rocking” problems with an apparatus may also result where the legs do not all contact the floor. Moreover, installations that are not level may be aesthetically undesirable by the inability to match the heights of adjacent cabinets, other equipment, or work surfaces.
Installers and manufacturers have attempted to resolve the leveling problem by developing approaches to compensate for uneven and sloping floors. Where the height of apparatus legs is not adjustable, for example, one such approach used by installers has been to place shims or wedges made of a suitable material under the legs. Obviously, this technique has numerous drawbacks. First, the apparatus must be manually lifted while such shims are placed under the legs, thereby often requiring more than one installer. This situation also increases the potential risk of back or other physical injuries to the installers. Second, the shims are not permanently mounted to the apparatus legs and may shift over time or become completely dislodged. This is especially problematic with motorized apparatuses which vibrate and “walk” as described above.
Manufacturers have attempted to resolve the leveling problem with numerous design approaches. One technique which has been employed is to provide manually adjustable legs or supports, often referred to commercially as glides or levelers, under each corner of the apparatus's outer cabinet. This consists primarily of a threaded vertical rod which on one end is screwed into a female threaded coupling near the apparatus's corners. The rod typically has a pad or flattened base of some sort disposed on the opposite end which contacts the floor. The pad may also swivel or tilt relative to the longitudinal axis of the vertical rod. These manually adjustable supports, however, are still plagued by many of the problems encountered with the shim technique described above. For example, in many cases, the apparatus must be lifted manually to unload weight from the legs in order to rotate them and adjust their height. Furthermore, there is usually no way to access the rear legs for adjustment once the apparatus is slid into its final position because access is often not available from the rear or sides of the apparatus. This is particularly true of kitchen appliances such as refrigerators and dishwashers which are usually placed against a wall in the rear and have other equipment, cabinets, or a wall positioned against one or both sides of the apparatus. The manually adjustable leg design is also cumbersome to use, involving a time consuming trial and error approach to leveling the apparatus on uneven floors. The apparatus must often be slid into and out of its final position numerous times while gradual adjustments are made to the otherwise inaccessible rear support legs in hopes of finding the proper height of each rear leg.
Other approaches have been used with limited success in an attempt to overcome the many problems of leveling objects on uneven floors. For example, U.S. Pat. No. 4,518,142 to Sulcek et al. discloses a leveling system for appliances utilizing manually adjustable wheels or rollers for rear supports. Even though the appliance may be easier to push into its final position, the height of the rear supports must be adjusted before the appliance is slid into place, often without access to the final resting position of the rear supports on the floor. U.S. Pat. No. 5,749,550 to Jackson discloses a rear leveling system for refrigerators using rollers for rear supports. Although the rear supports are adjustable from the front of the appliance, the mechanism is complicated and requires virtually all parts to be fabricated from metal. Like many similar mechanisms, the manufacturing costs are high and they are prone to problems due to their complex design.
Accordingly, there is a need for a leveling device that is simple in design, economical to produce, and allows adjustment of the height of the rear supports or legs after the object is in place.